New 300-Norma velocity ladder ...

[rustyinbend]

Just came back from the range after exercising my new MPA 300 Norma rifle. This velocity ladder was just too pretty not to share. Next steps are really obvious, with SD/Group testing planned at 84.5gr and 84.9. The last shot at 3050 ft/sec gave me the first hint of a heavy bolt, so I feel like I'm right in the sweet spot I was looking for.

 

[MOUNTIC]

Just came back from the range after exercising my new MPA 300 Norma rifle. This velocity ladder was just too pretty not to share. Next steps are really obvious, with SD/Group testing planned at 84.5gr and 84.9. The last shot at 3050 ft/sec gave me the first hint of a heavy bolt, so I feel like I'm right in the sweet spot I was looking for.

View attachment 7862986

What pills are you shooting?

 

[rustyinbend]

What pills are you shooting?

Well I'd "like" to be shooting Berger 220 LRHT's ... but they're rarer than hen's teeth (as my dad used to say) ... so I'm shooting Hornady 225 ELDM's and getting good results. I'm about to give up on Berger, and just switch over completely to Hornady.

 

[CanisLupus]

How many shots were taken at each charge weight, to generate the bars? Thanks.

 

[rustyinbend]

How many shots were taken at each charge weight, to generate the bars? Thanks.

It's a 10-shot ladder ... one shot at each charge weight.

 

[FrankinND]

Have you thought about using Sierra Bullets?

 

[kthomas]

It's a 10-shot ladder ... one shot at each charge weight.

 

[kthomas]

Good speeds, I can't push 230 Berger's any faster than 2950 fps before encountering pressure with 85.0 grains Retumbo.

I wouldn't read too much into data from 10-shot ladders though.

 

[robb_va]

Just came back from the range after exercising my new MPA 300 Norma rifle. This velocity ladder was just too pretty not to share. Next steps are really obvious, with SD/Group testing planned at 84.5gr and 84.9. The last shot at 3050 ft/sec gave me the first hint of a heavy bolt, so I feel like I'm right in the sweet spot I was looking for.

View attachment 7862986

Looks good. What length barrel? Thanks.

 

[Huskydriver]

Good speeds, I can't push 230 Berger's any faster than 2950 fps before encountering pressure with 85.0 grains Retumbo.

I wouldn't read too much into data from 10-shot ladders though.

@Mr. F just like my results

 

[robb_va]

@Mr. F just like my results

Same on this end. I got 3040 FPS (27") with 225 ELDM's and 86 grains. I had heavy bolt lift.

I switched back over to N570 and then later to RL33 and 250s.

 

[Feniks Technologies]

Good speeds, I can't push 230 Berger's any faster than 2950 fps before encountering pressure with 85.0 grains Retumbo.

I wouldn't read too much into data from 10-shot ladders though.

I’ve been running 230 Atips @ 2850

Not extremely fast, but the performance is pretty nice.

 

[rustyinbend]

Looks good. What length barrel? Thanks.

27 Inches ... with a Chimera-300 suppressor.

 

[rustyinbend]

Have you thought about using Sierra Bullets?

I have a whole bunch of Sierra MK 220's that I use for pills in my subsonic 300-BLK loads ... pondered those ... but if I can get a low SD and consistent velocities and good groups at distance from the H-225's, I'll probably declare victory and move forward with those.

 

[rustyinbend]

Same on this end. I got 3040 FPS (27") with 225 ELDM's and 86 grains. I had heavy bolt lift.

I switched back over to N570 and then later to RL33 and 250s.

Great idea ... I'll run right out to the store and stock up on RL33 ... um ... I'm sure I can find tons of it all over the place.

 

[rustyinbend]

I wouldn't read too much into data from 10-shot ladders though.

I don't read any more into it than it shows.

• 10 shots at .2 increments
• Gradual and predictable increase in velocity
• No pressure signs early
• Last shot showed pressure
• Two flat spots to investigate further

Why do you say this ... I'm curious. Would you have done 20 shots? Used larger or smaller increments? Interpreted the result differently? Do you think ladder tests of any kind are unreliable?

I've noticed a common statement in this forum is "You can't trust 10-shot ladder tests" ... but my findings actually indicate they're good prognosticators for next steps in the load development process.

My question back to you is ... What would you have done instead of this, to figure out next steps in your load development process?

 

[kthomas]

I don't read any more into it than it shows.

• 10 shots at .2 increments
• Gradual and predictable increase in velocity
• No pressure signs early
• Last shot showed pressure
• Two flat spots to investigate further

Why do you say this ... I'm curious. Would you have done 20 shots? Used larger or smaller increments? Interpreted the result differently? Do you think ladder tests of any kind are unreliable?

I've noticed a common statement in this forum is "You can't trust 10-shot ladder tests" ... but my findings actually indicate they're good prognosticators for next steps in the load development process.

My question back to you is ... What would you have done instead of this, to figure out next steps in your load development process?

Load up a few identical ladders, and see if those so-called "flat spots" still exist.

Ladders are great for getting an idea of approximate velocity and where pressure may be found. I perform ladders as well, for those two purposes.

However, you may find those "flat spots" don't really exist...

 

[rustyinbend]

Load up a few identical ladders, and see if those so-called "flat spots" still exist.

Ladders are great for getting an idea of approximate velocity and where pressure may be found. I perform ladders as well, for those two purposes.

However, you may find those "flat spots" don't really exist...

Understood ... BUT ... "IF" I load 10 rounds to a flat spot and get single-digit SD's and tight groups ... should I stop, or keep looking? I get what you're saying, but in our world of limited supplies and expensive components, knowing when to declare victory is important too. I've decided to load 10 rounds at 84.5 with Retumbo, and see if that 3000 ft/sec is (a) real, and (b) consistent. An SD of "5.0" with tight groups is usually my target. If I can get there, I load more, and test at distance (1,000 yards). If none of that works, I'll go back and try another ladder, or possibly different components. It's not a destination ... it's a journey ... right? At the end of the testing, I want this to be my 1-mile competition rifle load.

 

[kthomas]

Understood ... BUT ... "IF" I load 10 rounds to a flat spot and get single-digit SD's and tight groups ... should I stop, or keep looking? I get what you're saying, but in our world of limited supplies and expensive components, knowing when to declare victory is important too. I've decided to load 10 rounds at 84.5 with Retumbo, and see if that 3000 ft/sec is (a) real, and (b) consistent. An SD of "5.0" with tight groups is usually my target. If I can get there, I load more, and test at distance (1,000 yards). If none of that works, I'll go back and try another ladder, or possibly different components. It's not a destination ... it's a journey ... right? At the end of the testing, I want this to be my 1-mile competition rifle load.

SD of 5 is great. If that's what you get, rock on.

Honestly, these days it's hard to load bad ammo with quality components and reloading gear, using a repeatable process.

My point is that we try to look for conclusions in small data sets that don't actually exist. There probably isn't much of a difference between any of the charge weights, SD wise.

In all reality, there isn't probably any real velocity "nodes" or flat spots when compared to other charge weights you tested.

 

[rustyinbend]

OK ... now you've officially got me "curious". I'm going to reproduce that ladder exactly as before, and see what happens.

 

[Hoot owl hollow Dan]

I know this is kinda a old thread but I'm curious how the results of your rerun on the latter test came out.

I'm new here.. actually my first comment ever.

But I just broke-in a new rifle and was searching info on ladder pressure test to find nodes in my new rifle to conservative on components and time of which is in very short supply.

Any direction to more info on the subject would greatly be appreciated

 

[kthomas]

I know this is kinda a old thread but I'm curious how the results of your rerun on the latter test came out.

I'm new here.. actually my first comment ever.

But I just broke-in a new rifle and was searching info on ladder pressure test to find nodes in my new rifle to conservative on components and time of which is in very short supply.

Any direction to more info on the subject would greatly be appreciated

You won't find any so-called "nodes" with a ladder test.

But don't take my word for it, try it for yourself. Load up 2 or 3 identical ladders and see if any "nodes" found in the first ladder repeat in the other ladders.

 

[kthomas]

If you want single digit SD's, all you need is a repeatable reloading process with good quality equipment and components.

I don't need any load development to develop a load that has an SD of around 5.

 

[Hoot owl hollow Dan]

You won't find any so-called "nodes" with a ladder test.

But don't take my word for it, try it for yourself. Load up 2 or 3 identical ladders and see if any "nodes" found in the first ladder repeat in the other ladders.

Well bummer.. I'm guessing this video is one of the oldest on the subject. So I guess it's wishful thinking that it can be this easy?

 

[kthomas]

Well bummer.. I'm guessing this video is one of the oldest on the subject. So I guess it's wishful thinking that it can be this easy?

The ladder doesn't reveal any so-called "nodes" like some claim - this is easily proven by loading up a few identical ladders and testing yourself.

Reloaders tend to try and draw conclusions from statistically irrelevant sample sizes.

However, we tend to make reloading much more complicated than it needs to be. Reloading can be quite simple. Use good quality equipment (press, dies, powder thrower, etc), good quality components (Lapua brass, berger bullets, etc), and it can be quite simple to develop a high performing load.

 

[Hoot owl hollow Dan]

If you want single digit SD's, all you need is a repeatable reloading process with good quality equipment and components.

I don't need any load development to develop a load that has an SD of around 5.

I think I've got pretty good stuff.

New Howa 1500 in a bravo stock .

Quality brass,components and powder for 6.5 Creed.


Was hoping to make it quick..and conservative components.

Guess I need to rethink my approach.

 

[kthomas]

I think I've got pretty good stuff.

New Howa 1500 in a bravo stock .

Quality brass,components and powder for 6.5 Creed.


Was hoping to make it quick..and conservative components.

Guess I need to rethink my approach.

Berger Hybrids seated +/- 20 thou off the lands, and 42 grains H4350 +/- 0.5 grains (do a ladder to make sure you aren't running into pressure).

There you go.

 

[Hoot owl hollow Dan]

Wish I could find h4350. I found 1 pound in the past 6months. I scored 3 pounds of 6.5 staball and 300 hornady 140gr eld-m and 200 147eld-m hopefully my rifles likes the stuff .. I'm seeing pretty good info online for it .. but I hear h4350 is had to beat.

I'll stop here cuz, I don't want to hijack the original thread. Thanks for the info guys.

 

[Bacarrat]

Just finished ladder test with a 26" Proof. Settled on 84.5 grains. Had several groups in the 85.5gr area in the sub .200" MOA but was getting a click so I backed it off. I'll verify the loads in the morning but don't think too much will change at distance.

 

[babyguppy]

OK ... now you've officially got me "curious". I'm going to reproduce that ladder exactly as before, and see what happens.

sorry to revive an older thread .. but my curiosity is getting to me.
Rusty, did you redo the ladder to see if you replicated the previous findings?
Thanks,

 

[Conqueror]

Most people don’t. Real statisticians would be horrified at a lot of the practices in the reloading community.

To me the use of the ladder is to see if your chosen powder will get you to your desired velocity, and to see what charge results in pressure signs in your rifle. I don’t think it identifies nodes very well and honestly I’m not 100% convinced that harmonic nodes have to be where you load to. Find your desired velocity with the ladder, or drop 0.2-0.4 from pressure signs, and just try loading 10-20 at that charge weight to see what your SDs look like.

 

[rustyinbend]

sorry to revive an older thread .. but my curiosity is getting to me.
Rusty, did you redo the ladder to see if you replicated the previous findings?
Thanks,

I did try it, and the result was actually more pressure signs at the lower numbers. Decided to go in a slightly different direction and build a ladder with H1000 instead of Retumbo. The results were good, and two ladders in a row pointed me to around 79.2 grains of H1000 for velocities around 2900 and really nice SD's and tight groups. Here's 15 that I shot last month before the weather got ugly. Average velocity of 2884 and a SD of 6.35. Next range day I'll go out to 1400 yards and see how the BC holds up ... at 200 yards the BC calculated to .337 (manufacturer's BC is .364).

Using ladders now to find good spots to settle on powder charge and test "other stuff" mostly around neck tension and seating force.

I've also just today received my new AMP Press (Woohoo), so I'll be able to get more precision and consistency around bullet seating ... so that's on the agenda too. Just need more good weather range days, and fewer honey-do list items.